Heart attacks limit local oxygen, which can kill areas of cardiac tissue — called ‘infarcted’ areas — and also leave scarring. This damage leads to a lack of synchrony in the heart beat motion.

Overcoming limits of pacemakers

Current therapies use pacing devices, but these require healthy tissue for optimal outcome, meaning a third of patients do not respond well to this treatment. This new approach overcomes this limitation, since stem cells actually form functional cardiac tissue and reconstruct heart muscle.

Professor Andre Terzic, who led the study, explains the importance of this potential new therapy: “Heart chambers must beat in synchrony to ensure proper pumping performance. Damage to the heart can generate inconsistent wall motion, leading to life-threatening organ failure.

“The heart is vulnerable to injury due to a limited capacity for self-repair. Current therapies are unable to repair damaged cardiac tissue. This proof-of-principle study provides evidence that a stem cell-based regenerative intervention may prove effective in synchronizing failing hearts, extending the reach of currently available therapies.”

Doctor Satsuki Yamada, first author of the study, further explains how the research was carried out: “Stem cells, with a capacity of generating new heart muscle, were engineered from ordinary tissue. These engineered stem cells were injected into damaged hearts of mice. The impact on cardiac resynchronization was documented using high-resolution imaging.”

The observed benefit, in the absence of adverse effects, will need to be validated in additional pre-clinical studies prior to clinical translation.